Diazotype light-sensitive copying papers intended for wet development and for use in the preparation of intermediates

ABSTRACT

A diazo-type copying paper which is prepared by coating, on a light-transmitting base, a light-sensitive composite containing a diazonium compound obtained from 1-amino-4-dialkylaminomonochloro benzene and also containing a coupling component consisting of 2-alkyl-5-alkyl-4-morpholino-methyl-phenol, provides an excellent intermediate copy when developed according to the wet development process.

United States Patent [72] inventor [2 l 1 Appl. No. [22] Filed 45 Patented [73 Assignee [54] DIAZOTYPE LIGHT-SENSITIVE COPYING PAPERS INTENDED FOR WET DEVELOPMENT AND FOR USE IN THE PREPARATION OF INTERMEDIATES 3 Claims, No Drawings [52] US. Cl. 96/49, 96/91 [51 Int. Cl G03c 5/34, G03c 1/58,G03c 1/54 [50] Field of Search 96/49, 75, 91

[56] References Cited UNITED STATES PATENTS 2,298,444 10/1942 Weissbergeretai 96/91 2,793,118 5/1957 Sanders et a1 96/91 2,946,684 7/ 1960 Sus et a1 96/91 FOREIGN PATENTS 628,914 9/1949 Great Britain..; 7 96/91 71 1,390 6/1954 Great Britain 96/91 808,527 2/1959 Great Britain 6/91 OTHER REFERENCES Dinaburg; M. S., Photosensitive Diazo Compounds, 1964, pp. 60- 62.

Primary Examiner-Charles L, Bowers, .lr. Attorney-Woodhams, Blanchard and Flynn ABSTRACT: A diazo-type copying paper which is prepared by coating, on a light-transmitting base, a light-sensitive composite containing a diazonium compound obtained from 1- amino-4-dia1kylamino-monochloro benzene and also containing a coupling component consisting of 2-alkyl-5-alkyl-4- morpholino-methyl-phenol, provides an excellent intermediate copy when developed according to the wet development process.

DIAZOTYPE LIGHT-SENSITIVE COPYING PAPERS INTENDED FOR WET DEVELOPMENT AND FOR USE IN THE PREPARATION OF INTERMEDIATES BACKGROUND OF THE INVENTION l. Field of the Invention The present invention is concerned with a diazo-type copying paper which can be applied to the wet development process, and more particularly, it relates to a light-sensitive diazo-type copying paper intended for use in the preparation of an intermediate which can be utilized as the second original for the diazo-type copying papers.

2. Description of the Prior Art Diazo-type copying papers for use in the preparation of intermediates are made by the use of light-transmitting sheet materials serving as the base sheets and by coating them, on one surface of each sheet, with a combination of a light-sensitive diazo compound and an azo dye coupling component which is adapted to couple with said diazo compound to form an azo dye which is capable of blocking the actinic light to pass therethrough. Most of those conventional diazo-type copying papers intended for the preparation of intermediates are so designed as to be developed according to the so-called dry development process which utilizes ammonia gas. On the other hand, a number of attempts have been made in the past, as a matter of fact, to work out diazo-type copying papers which would be developed according to the wet development process to produce intermediate copies. However, one of these prior attempts has succeeded in producing a copying paper which could practically satisfy this purpose. One major reason for this failure in the past lies in the fact that the conventional diazo-type copying papers intended for the preparation of intermediates required the use of a specifically designed liquid developer which was different from those developers intended for use in the development of ordinary diazo-type copying papers. For this reason, it was necessary that in each developing operation the developer which has been used in the development of a copying paper intended for use as an intermediate be replaced by a different developer in order to produce copies by using the developed intermediate as the second original. Also, those conventional diazo-type copying papers which were intended for the preparation of intermediates by the wet development process and which were so designed as could be developed by an ordinary liquid developer had the inconveniences that the light-sensitive diazo compound and the coupling component which were both contained in the light-sensitive layer were coupled at a low coupling velocity during the development process, and further that the portions of the copied image formed on the copying paper lacked the property of sufficiently blocking the actinic light to pass therethrough. This constituted another important reason why the conventional diazo-type copying papers intended for the preparation of intermediates were not satisfactory.

SUMMARY OF THE INVENTION It is, therefore. the object of the present invention to eliminate all of the the various drawbacks and inconveniences of the aforesaid conventional diazo-type copying papers intended for the preparation of intermediates, by the employment of specific diazo compounds and specific coupling components in the formation of the light-sensitive layers of the copying papers.

More particularly, the present invention contemplates the provision of an improved diazo-type copying paper intended for the wet development process and for use in the preparation of an intermediate copy, by forming, on one surface of a light-transmitting support sheet, a light-sensitive layer containing a diazo compound consisting of 4-dialkylaminomonochloro-benzene diazonium compound and a coupling component consisting of 2-alkyl-5alkyl-4-morpholinomethyl-phenol.

The diazo compounds and the coupling components which are employed in the present invention have a property that they quickly couple to each other in an alkaline aqueous solution having a pH value ranging from 6 to 10. preferably 8 to l0, to produce an yellow azo dye which has a highly increased ability of blocking the actinic light. Accordingly, the light-sensitive copying paper which is obtained according to the present invention and which is used in the preparation of an intermediate copy can be developed sufficiently by the use of an ordinary liquid developer which is intended for the development of ordinary diazo-type copying papers. In case, however, the light-sensitive copying paper of the present invention is developed by an ordinary liquid developer which is intended for the development of ordinary diazo-type copying papers and which usually contains a coupling component, the developed copied image will bear an yellowish brown color or a brown color owing to the influence of the azo dye which is formed as the result of the coupling of said coupling com-l ponent contained in the liquid developer to the diazo com-i pound contained in the light-sensitive layer of the copying paper. It is to be noted, however, that the portions of this developed copied image which bear such a color are also capable of blocking the actinic light.

The diazo compounds which are applied to the present invention and which are generally called 4-dialkylaminomonochloro-benzene diazonium compounds are expressed generally by the following chemical formula:

wherein: R represents a radical selected from the group consisting of methyl radicals and ethyl radicals, and

X represents an anionic acid radical.

These diazo compounds are prepared by diazotizing l-amino- 4-dialkylamino-monochloro-benzene according to the known diazotizing process. These diazo compounds include the following ones:

4-dimethylamino-2-chloro-benzene diazonium chloride zinc chloride double salt,

4-dimethylamino-3-chloro-benzene diazonium chloride zinc chloride double salt,

4-diethylamino-2-chloro-benzene diazonium chloride zinc chloride double salt, and

4-diethylamino-3-chloro-benzene diazonium chloride zinc chloride double salt These diazo compounds are normally of the nature to couple to the coupling components with a very high velocity. Accordingly, in the event that such a diazo compound is used in the so-called two-component type copying paper which contains both this diazo compound and a coupling component in its light-sensitive layer, the resulting copying paper will tend to give rise to the pre-coupling phenomenon. For this reason, these diazo compounds were not utilized in the preparation of the two-component type copying papers. The present invention, however, has successfully solved this problem by the fact that it employs a coupling component having a specific composition.

The coupling components which are applied to the present invention and which are, in general, called 2-alkyl-5-alkyl-4- morpholino-methyl-phenol are expressed generally by the following chemical formula:

CH CH R N-CHz- R, wherein: R and R represent alkyl radicals having 1 to 4 carbon atoms.

These coupling components include the following substances:

2,S-diethyl4-morpholino-methyl-phenol, 2,5dimethyl4-morpholino-methyl-phenol, 2,5dibutyl-4-morpholino-methyl-phenol, 2,5dipropyl-4-morpholio-methyl-phenol, 2-methyl5ethyl-4-morpholino-methyl-phenol, and 2-ethyl-5-propyl-4morpholino-methyl-phenol.

These coupling components are of the nature that they are easily dissolved in acid aqueous solutions and that they are hardly soluble in neutral and alkaline aqueous solutions. Also, these coupling components are of the nature of rapidly couple to diazo compounds when contacted by an alkaline aqueous solution and to thereby form azo dyes. The azo dyes thus formed will hardly be dissolved in a neutral aqueous solution as well as in alkaline aqueous solution.

From the foregoing detailed description, it will be understood that the diazo-type copying paper of the present invention which is prepared by coating one surface of a lighttransmitting base sheet with a combination of the aforesaid specific diazo compound and said specific coupling component is of a highly improved shelf life and also that the azo dye which is formed on said copying paper is of a highly improved resistance to weather and has a superior property of blocking the actinic light. As such, the diazo-type light-sensitive copying paper of the present invention is of a sufficient adaptability for being used as an intermediate for diazo-type copying papers.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Example I A solution having the following composition:

Water I000 cc. Citric acid It) g. Sulfosalicylic acid It) g. Concentrated sulfuric acid 1 cc. lsopropyl alcohol l cc. 4-dicthylamino-Z-chloro-henzcnc diazonium chloride zinc chloride double salt 20 g 2.5-dimcthyl-4-morpholinomcthyl-phenol HCI 26 g. Saponin l g. Methylene Blue 0.07 g.

was applied on one surface ofa tracing paper of 75 g./m. and was dried to prepare a light-sensitive copying paper. This copying paper was then exposed to light through an appropriate original placed on the light-sensitive layer thereof by the use of a copying apparatus provided with a fluorescent lamp of 60 Watts. By developing this exposed copying paper with a liquid developer having the following composition and being intended for developing images of a violet color, there was obtained an intermediate carrying a copied image of a brown color which had a highly increased ability of blocking actinic light, and said intermediate was suitable for use as the second original for diazo-type copying papers. Said composition of the liquid developer used in this instant example was:

Water llltll) cc. (austic potash It) g. Potassium tetrahorate 30 g. Thiourea 21) g. Sodium l-naphtol-J-suli'onatc It) g.

Water lOUi) cc. Citric acid [0 g. Sulfosalicylic acid g. Concentrated sulfuric acid I cc. lsopropyl alcohol ll) cc. 4-dimethylamino-J-chlortrbenzene diazonium chloride zinc chloride douhle salt g. Z-methyl-S-ethyl-4-morpho|inomethyl-phenol HCI 28 g. Saponin l g. Methylene Blue 0.07 g

and in a manner similar to that described in example l a copying paper was prepared. This copying paper was noted to be as satisfactory as that obtained in example l when used as an intermediate for diazo-type copying papers. Example 3 By developing the copying paper obtained in example I with a liquid developer which was intended for developing image in black color and which had the following composition, there was obtained an intermediate carrying a dark brown copied image and being suitable for use as the second original for diazo-type copying papers. Using this intermediate as the original, an ordinary diazo-type copying paper for developing black color was exposed to light through this original placed thereon, and the exposed copying paper was developed by the use of the aforesaid liquid developer. As a result, a satisfactory copy carrying a black copied image was obtained. The composition of said liquid developer was:

Water I000 cc.

Citric acid I g.

Sodium citrate 30 g.

Sodium henzonate 20 g.

Sodium formatc l5 g.

Chloroglycine 4 g.

Example 4 By developing a color on the copying paper obtained in example l by the use of a liquid developer intended for developing a blue color image and having the following composition. there was obtained an intermediate carrying a yellowish black copied image and being suitable as a second original for diazotype copying papers. Using this intermediate as the original, an ordinary diazo-type copying paper for use in developing a blue color was exposed to light through this original placed thereon, and the exposed copying paper was developed with the aforesaid developer. As a result, a copy of superior quality was obtained. The composition of said liquid developer was:

Water ltlllt) cc. Caustic potash [2 g. Potassium tctrahorate 30 g. Thiourea 30 g. Potassium chloride 30 g. Z-hydrtixy-3-ntiphthtiic acid hydroxy-ethylamine 8 g.

Example 5 By using a solution having the same composition as that of example 1 with the exception that the diazo compound used was 20 g. of 4-diethylamino-3-chloro-ben2ene diazonium chloride zinc chloride double salt instead of 4-diethylamino- 2chloro-benzene diazonium chloride zinc chloride double salt, an intermediate for diazo-type copying papers was produced. This intermediatewas noted to have properties which were comparable to the one obtained in example l Example 6 Using a solution having the same composition as that used in example 1 with the exception that the coupling component used consisted of 30 g. of 2,5-dibutyl-4-morpholino-methylphenol HCI in lieu of 2,5-dimethyl-4-morpholino-methylphenol HCI. an intermediate for diazo-type copying papers was obtained. Like the one described in example I, this intermediate satisfied the requirements for a second copy.

Saponin l g.

was applied onto one surface of a thick tracing paper, and was dried to prepare a light-sensitive copying paper. This copying paper was exposed, through an appropriate original, to a light Water I000 cc. Caustic potash l g. Potassium Tetraborate 30 g. Thiourea 20 g. Sodium l-naphtol-4-sulfonatc l5 g.

Not only this intermediate copy, but also the copying paper prior to the exposure were both found to be superior in their shelf lives. In addition, there was noted no azo dye which came off from the exposed copying paper during the process of development. Example 8 After exposing the copying paper obtained in example 7 to light, the same was developed with an alkaline aqueous solution having the following composition:

Water I000 cc. Caustic potash [2 g. Potassium tctraboratc 30 g. Thiourea g.

As a result, an intermediate copy carrying an yellowish green copied image having a highly increased ability of blocking actinic light was obtained.

What is claimed is:

l. A process for making a diazo-type intermediate copy which comprises the steps of:

exposing to actinic radiation a diazo-type light-sensitive copying paper on which is superposed an image-bearing original, said copying paper comprising a light transmitting base having one surface coated with a light-sensitive composition containing an acid stabilizer, a light-sensitive diazo compound having the following formula:

/N N1X R I wherein: R is an alkyl radical having I or 2 carbon atoms,

and X is an anionic acid radical, and further containing a coupling component having the following formula:

R1 GET-CH1 N-CHgwherein: each of R, and R is an alkyl radical having I to 4 carbon atoms;

and then treating said copying material with an aqueous alkaline developing solution to develop an image capable of blocking actinic light.

2. A process according to claim 1, wherein said diazo compound is selected from the group consisting of 4- dimethylamino-2-chloro-benzene diazonium compound, 4- dimethylamino-3-chloro-benzene diazonium compound, 4- diethylamino-Z-chloro-benzene diazonium compound and 4- diethylamino-3-chloro-benzene diazonium compound.

3. A process according to claim I, wherein said coupling component is selected from the group consisting of 2,5- dimethyl-4-morpholino-methyl-phenol. 2.5-diethyl4- morpholino-methyl-phenol, 2,5-dipropyl-4-morpholinomethyl-phenol, 2,5-dibutyl-4-morpholino-methyl-phenol, 2- methyl-5-ethyl-4-morpholino-methyl-phenol and 2-ethyl-5- propyl-4-morpholino-methyl-phenol. 

2. A process according to claim 1, wherein said diazo compound is selected from the group consisting of 4-dimethylAmino-2-chloro-benzene diazonium compound, 4-dimethylamino-3-chloro-benzene diazonium compound, 4-diethylamino-2-chloro-benzene diazonium compound and 4-diethylamino-3-chloro-benzene diazonium compound.
 3. A process according to claim 1, wherein said coupling component is selected from the group consisting of 2,5-dimethyl-4-morpholino-methyl-phenol, 2,5-diethyl-4-morpholino-methyl-phenol, 2,5-dipropyl-4-morpholino-methyl-phenol, 2,5-dibutyl-4-morpholino-methyl-phenol, 2-methyl-5-ethyl-4-morpholino-methyl-phenol and 2-ethyl-5-propyl-4-morpholino-methyl-phenol. 